We evaluated 34 total hip arthroplasties (THA) for avascular necrosis of the femoral head in 26 patients who were younger than 40 years at the time of the index operation. The average age at the time of THA was 283 (17-38) years. The mean follow-up was 10.9 (5-19) years. We used 6 cemented and 28 cementless acetabular components and a cemented polished tapered stem in all hips. The mean Charnle...

Locking mechanisms and metal-liner interface surfaces of six modular acetabular systems were evaluated to determine their effect on micromotion and backside wear of the polyethylene liner. Rotational and axial motion between the metal shell and polyethylene liner was measured in the Duraloc (DePuy, Warsaw, IN), Harris-Galante (Zimmer, Warsaw, IN), Impact (Biomet, Warsaw, IN), Lip Loc (Biomet), ...

In recent years, hydroforming process has been applied in different industries such as aerospace, automotive and military industries due to its advantages, such as high dimensional accuracy, capability of forming complicated parts and high drawing ratio. Hydrodynamic deep drawing with radial pressure is one type of hydroforming process. In this paper, forming of cylindrical cups in hydrodynamic...

Background Several 2-dimensional and 3-dimensional surfaces are available for cementless acetabular fixation. Plain radiographs are used to assess osseointegration; however, the radiographs are limited by their inability to capture the bone fixation process occurring over the 3-dimensional cup surface. In this cadaveric study, we compared the bone apposition between 2-dimensional and 3-dimensio...

Information is sparse on the role of foods in long-term blood pressure (BP) change. The investigators examined relations of food intake to BP change in a prospective cohort study of 1,710 employed men in Chicago, Illinois, initially aged 41-57 years. In 1958 and 1959, BP was measured and nutrient intake assessed by comprehensive interview. In 1959, intake of 26 specific food groups was also ass...

Prospectively the outcome after total hip replacement with a new threaded acetabular cup design was compared to an established press-fit cup. After 1, 2 and 5 years, the 36-item Short Form Health Survey, Western Ontario and McMaster University Osteoarthritis Index and Harris Hip Score revealed no significant differences between the two groups (each group : n = 42 patients), except for a higher ...

Leber congenital amaurosis (LCA) is an inherited retinal dystrophy that causes childhood blindness. Photoreceptors are especially sensitive to an intronic mutation in the cilia-related gene CEP290, which causes missplicing and premature termination, but the basis of this sensitivity is unclear. Here, we generated differentiated photoreceptors in three-dimensional optic cups and retinal pigment ...

An element a of a lattice cups to an element b > a if there is a c < b such that a∪c = b. An element of a lattice has the cupping property if it cups to every element above it. We prove that there are non-zero honest elementary degrees that do not have the cupping property, which answers a question of Kristiansen, Schlage-Puchta, and Weiermann [17]. In fact, we show that if b is a sufficiently ...

The cup drawing is a basic deep drawing process. Thus, understanding the mechanics ofthe cup drawing process helps in determining the general parameters that affect the deep drawingprocess. There are mainly two methods of analysis; experimental and analytical/numerical.Experimental analysis can be useful in analyzing the process to determine the process parameters thatproduce a defect free prod...

We performed thermal analysis of polyethylene samples obtained from 73 new cups of the Weller hip prosthesis. There were marked individual differences in the degree of their crystallinity, ranging from 37.8% to 67.2% with a mean of 53%. Analysis of polyethylene from removed cups also showed differences in crystallinity in individual cups, with the mean value being higher in the removed implants...